Arsenal have work to do if they are to reach the Champions League quarter-finals for the first time in 14 years after falling to a stoppage time winner against Porto in their last 16 first leg.

Porto winger Galeno scored a stunning strike from distance with virtually the last kick of the game to decide a contest that never really got going over the course of the preceding 93 minutes.

It leaves Arsenal with a 1-0 aggregate deficit to overturn at the Emirates Stadium next month.

After a nervy opening five minutes, Arsenal soon dominated the ball, yet Porto’s defensive organisation and resilience was clear to see. The Gunners were frustrated, with every avenue seemingly blocked and not even a remote sign of a chance, let alone a goal.

Indeed, the first shot from either side came midway through the first half and went to Porto. It was remarkable that the hosts didn’t go ahead in that moment, with Galeno drifting into the box from the left flank and rattling a half volley against the post from close-range. The rebound went straight back to the Brazilian, but unable to readjust, he fired narrowly wide with the goal gaping.

Arsenal’s first attempt of any kind eventually followed 33 minutes in, with Leandro Trossard firing well over from the left-hand side of the penalty area. William Saliba and Kai Havertz each missed with headers from corners, failing to register a single shot on target by the time the half ended. That was something that, frustratingly for those of a London persuasion, didn’t change by full-time.

Another corner presented Arsenal with the first real chance of the second half as Trossard met a cross deliberately floated to the back post, only to blaze over. Porto had a glorious chance of their own in the 66th minute when Pepe left Havertz for dead on the right and cut the ball back to Evanilson. The Gunners had Declan Rice to thank for stepping across just in time to deflect wide.

Overall, a positive tempo in the early stages of the second half ultimately waned long before Galeno’s sensational winner sent the Etadio do Dragao wild, just moments after Gabriel went close with a stoppage time header for Arsenal. But while a world class strike from the Porto star, floating a curling effort from distance into the far right top corner, the opportunity was presented when the young Gunners naively gave the ball away trying to counter attack at the death.

GK: David Raya – 6/10 – Might have expected to be busier but stood no chance for the late goal.

RB: Ben White – 6/10 – Tried as best he could to make himself a nuisance at attacking set-pieces.

CB: William Saliba – 5/10 – Seemed a little off his game and could have made up for that with a goal, only to miss with a header when he knew he should have hit the target.

CB: Gabriel Magalhaes – 5/10 – Won’t be happy that he won so few of his individual duels. Missed a good chance moments before Arsenal fell behind.

LB: Jakub Kiwior – 5/10 – Decent in possession but too weak in the tackle.

CM: Martin Odegaard (c) – 5/10 – Barely misplaced a pass but it felt like that didn’t achieve much.

CM: Declan Rice – 7/10 – Carrying a booking from literally the opening seconds but managed himself very well and still made vital defensive interventions. Arguably should have got tighter to Galeno.

CM: Kai Havertz – 6/10 – Alternated with Trossard in open play and took up very deliberate far-post positioning at a number of corners.

RW: Bukayo Saka – 5/10 – Delivered some teasing corners but had limited impact otherwise.

ST: Leandro Trossard – 5/10 – Too much on the periphery of the game. Missed a great chance.

LW: Gabriel Martinelli – 4/10 – Never left the pocket of his marker and was later guilty of losing the ball cheaply right before Porto scored.

SUB: Jorginho (74′ for Trossard) – 5/10

Subs not used: Aaron Ramsdale (GK), Karl Hein (GK), Cedric Soares, Ayden Heaven, Mohamed Elneny, James Sweet, Fabio Vieira, Ethan Nwaneri, Eddie Nketiah

Mikel Arteta – 6/10 – Set up his team with clear set-piece instructions but open play creativity, partly due to Porto’s defensive strength, was lacking. Hands tied by injuries and a weak bench.